Draw a closed polyline of the roof contour. (see picture)
Note: Measures are in meters.
Put it in an isometric view.
Extrude the polyline as text in the picture
If you want a roof with an inclination of 15 degrees you must introduce in the taper angle 90 –15 = 75 .
Now we need to close the top of the roof. How!
Using the Solids Editing toolbar we will chose Offset Faces.
And then we will proceed as in the following picture
We can get one of these results…
Or to Offset faces only 1 meter and then the result will be this
Use your imagination to explore the potential of AutoCAD.
You can find this Tip the in Portuguese in the AUGI's Portuguese Forum
Pode encontrar esta Dica em Português no Forum em Português do AUGI
If necessary I can explain how to obtain the 2D from the 3D Model using the SOLVIEW and SOLDRAW commands.